Idle Control Valve

[jarance]

Thanks so much Jarance!!

Can I take the ICV out and spray it with WD40?

Can the car run without the ICV? Will the FC be higher? When I disconnect the ICV, the car still run and rpm is stable

Many people still think the ICV is servicable. I don't think it can cos it is a regulating type. i.e. the control of air is regulate by opening and closing of the valve at a regular interval.

Yes the car can run without the ICV but your idling speed would be erractic.

When you disconnect the ICV, the RPM is stable!!! What is the RPM? Did you have any other device connected or did you tighten the throttle cable very tight such like you are simulating your foot slight rested on the fuel pedal.

BTW, ICV does not affect the FC. It only regulate the small amount of air into the throttle body to achieve stable idling speed. When the engine or car is moving fast, the ICV is basically switch off by the ECU.

 

[anaksarawak]

My rpm without the IRV is 850 and can be 1000 if I increase the trottle cable. The rpm is stable, only effect is when the gear is engaged the rpm did compensate it just drop 200 from 850 to 650 and when that happen.. I just have it at 1000 so it will drop to 800.

The reason why I am complaint as my car will virbrate like OSIM Chairs Hahaha! No matter how high I adjust the trottle the IRV will bring the RPM down to 650 and at 650 my car will vibrate especially when gear is on.

Many thanks for your help.

 

[jarance]

geoff, it does sound that you do have an ICV problem. Recommend that you swap it with a good ICV and test the car again.

Another thing that you should look at is the engine mounting. When it is worn out, vibration is noticeable at low rpm.

 

[anaksarawak]

geoff, it does sound that you do have an ICV problem. Recommend that you swap it with a good ICV and test the car again.

Another thing that you should look at is the engine mounting. When it is worn out, vibration is noticeable at low rpm.

Engine mounting and gearbox mounting are fixed. Will try your advice to check on the IRV.

Many thanks for extending the help outside of Tech and Performance, I really appreciate it

 

[anaksarawak]

At last.. found the problem.. leaking return vacuum hose. Job done RM25

Learn from many other forumers that the followings can also be the suspect for car vibrating.

1. spark plugs (old)
2. Spark plugs cable
3. AFM (air flow meter)
4. ICV or IRV
5. Engine and gearbox mounting
6. low engine compression
7. gearbox problem
8. Fuel pump,
9. Fuel filter and fuel regulator
10. leak vacuum hose
11. many more..


Thanks

 

[K.M.]

Geoff,

Where is this return vacuum hose?

 

[anaksarawak]

Item is no 8

 

[K.M.]

Thanks a lot Geoff. Need to look at mine also.